The present invention relates to a device for the automated installation, by means of helicopters, of marker balls on overhead lines, such as power lines, mountain telferages, cableways and the like.
The considerable increase in air traffic, even at low altitudes, by aircrafts such as helicopters, small leisure aeroplanes, ultralight aircraft for sports use and the like, has made mandatory the marking of the cables of overhead lines used for any purpose.
In particular, currently applicable laws mandate the visual marking of the cables of power lines when their height from the ground exceeds 50 meters and of mountain telferages if they are located at elevations in excess of four meters from the top of the underlying wooded areas.
As is known, the visual marking of overhead lines is performed by means of variously colored balls which are coupled onto the cable and, for this purpose, are constituted by two half-spheres made of polymeric material or the like, provided with elements for mutual snap-together coupling, for example mutually cooperating hooks and slots.
The installation of said marking means on existing facilities is usually performed with the aid of helicopters, the use whereof is moreover indispensable in the case of power lines, along which personnel cannot move once they are live and which, on the other hand, cannot be deactivated for a long time, both for economical reasons and for requirements of continuity of the service.
Installation is currently performed by highly specialized operators, who are suspended from the helicopter in stationary flight and manually perform the installation of each ball on the cables of the line.
These are obviously slow, very expensive operations which are subject to considerable risks and for which the use of twin-engine helicopters is strictly prescribed in order to reduce the risks arising from malfunctions.